Analysis of a dynamic, decentralized exchange economy

A model of a dynamic exchange economy is presented. Similarly to the Walrasian equilibrium problem, each consumer is characterized by a feasible set and by an instantaneous demand function, that depends on the price vector, time, and the commodity holding. The commodity holding of each consumer varies, at each moment, according to this instantaneous demand function. We show that the market can choose prices that keep the commodity holding of each consumer within his consumption set, while ensuring that the aggregate commodity holding satisfies the scarcity constraints of the market.     

Investment dynamics in electricity markets

We investigate the incentives for investments in capacity in a simple strategic dynamic model with random demand growth. We construct non-collusive Markovian equilibria where the firms?? decisions depend on the current capacity stock only. The firms maintain small reserve margins and high market prices, and extract large rents. In some equilibria, rationing occurs with positive probability, so the market mechanism does not ensure ??security of supply??. Usually, the price cap reflects the value of lost energy or lost load (VOLL) that consumers place on severely reducing consumption on short notice. Our analysis identifies a minimum price cap, unrelated to the VOLL, that allows the firms to recoup their investment and production costs in equilibrium. However, raising the price cap above this minimum increases market prices and reduces consumer surplus, without affecting the level of investment.     

Strategic Pricing when Electricity is Storable

In this paper, we develop a simplified oligopoly model where hydro generators engage in dynamic Bertrand competition. Each player uses a Markov strategy based on the state of water reservoirs at the beginning of each period. The replenishing of water reservoirs, which affects generators' productive capacity, is governed by a stochastic process. Also, a price cap, i.e. a maximum bid allowed, is imposed on the market. We develop valuable insights for regulatory policy in predominantly hydro based electricity markets, including the effects of price caps, the efficiency of dispatch under strategic behavior and the likelihood of collusion.     

Fluctuations in convex models of endogenous growth, I: Growth effects

Is there a trade-off between fluctuations and growth? The empirical evidence is mixed, with some studies finding a positive relationship, while others find a negative one. Our objectives are to understand how fundamental uncertainty affects the long run growth rate and to identify important factors determining this relationship in a convex endogenous growth model. Qualitatively, we show that the relationship between volatility in fundamentals (or policies) and mean growth can be either positive or negative. The curvature of the utility function is a key parameter that determines the sign of the relationship. Quantitatively, an increase in uncertainty always increases the growth rate in our calibrated models. Though the changes we find are nontrivial, they are not large enough by themselves to account for the large differences in growth rates observed in the data. We also find that differences in the curvature of preferences have very substantial effects on the estimated variability of stationary objects like the consumption–output ratio and hours worked. For this reason, we expect that the models considered in this paper will provide the basis of sharp estimates of the curvature parameter.